Dampener pad with liquid supply control for lithographic rotary printing presses



March 29, 1966 G. R. GATES 3,242,856

DAMPENER PAD WITH LIQUID SUPPLY CONTROL FOR LITHOGRAPHIC ROTARY PRINTINGPRESSES Eilecl Jan. 2, 1964 2 Sheets-Sheet 1 Inventor Maw In; 02%

March 29, 1966 A. G. R. GATES 3,242,856

DAMPENER PAD WITH LIQUID SUPPLY CONTROL FOR LITHOGRAPHIC ROTARY PRINTINGPRESSES Filed Jan. 2, 1964 2 Sheets-Sheet 2 Filed Jan. 2, 1964, Ser. No.335,324 Claims priority, application Great Britain, Jan. 4, 1963,

3 11 Claims. (Cl. 101-147) This invention concerns offset rotaryprinting machines which conventionally comprise a plate cylinder, ablanket cylinder, an impression cylinder, a delivery cylinder and meansforapplying ink and water to the plate cylinder. In ofi'set rotaryprinting machines, it is necessary, before commencement of the printingoperation, to apply to the plate an aqueous ink repellent solution whichdesensitizes the hon-image areas of the plate. This operation maybe'called""priming. For efiicient operation of the machine, it isessential that a really thoroughapplication of priming solution beeffected. It is also necessary in lithographic printing that the plateduring the printing operation be alternately inked or damped. Thisdampen ing can be carried out with either plain water or a dilutedsolution ofthe type employed for priming. i The devices employed fordampening during printing are not efficient to a high enough degree tocarry out a priming operation. Consequently, priming has generallybeen'carried out manually by the operator of the machine wiping acrossthe plate an absorbent pad soaked in the priming'solution. Such anoperation is time consuming and unpleasant for the operator.

Devices for dampening are known in which a pad or roller is movablebetween a position in which the pad or roller engages a plate on theplate cylinder and an out-ofthe way position in which the pad or rolleris spaced from the plate cylinder. Itis also known for such pad orroller to have'associated therewith a reservoir from which dampeningliquid is transferred to the pad or roller and for the afrangernentto besuch that liquid is not so transferredfromthe reservoirwhen the pad orroller is in the outof-the way position. Such devices suffer from thedisadvantages that the degree of dampening of the pad or or. roller isnot constant and considerable evaporation from the reservoir occurs.

1 It is an object of this invention to provide an apparatus capable ofapplying a priming solution to a plate quickly and efiiciently andwithout the operator having to handle the priming solution,

According "to this invention, the apparatus comprises a tube whichextends across the machine adjacent the plate cylinder and over which iswrapped a priming pad of a suitable priming solution absorbent material,the tube having perforations over at least a part thereof covered bysaid pad, means for moving the tube between an operative position inwhich the priming pad contacts the plate eylinde'r across the widththereof and an out-of-the way position in which said pad is spaced fromthe plate cylinder, and a reservoir for priming solution having at itsUnited States Patent lower part a valve from which a pipe leads to theinterior of said tube, the arrangement being such that the reservoirconstitutes a drip feed system for the interior of the tube, solutionlost from the latter through said perforations in replacing that removedfrom the pad in priming and evaporation being replaced by solutiondripping from said valve into the pipe due to reduction in pressuretherein, said valve being coupled to said tube so that the valve closeswhen the tube moves to its out-of-the-way position.

It will be appreciated that, in use of the apparatus according to thisinvention, the pad is when the tube is in its "Ice operative position,kept replenished with priming solution to a constant degree, but that,when the tube is in its outof-the-way position, the supply of primingsolution is cut off. Further with this form of feed the reservoir can beof relatively closed form and evaporation therefrom reduced.

The said valve may be of any suitable form, but is conveniently a rotaryplug valve. The reservoir may conveniently be in the form of an upturnedbottle having said valve in its neck and a filler cap with vent in itsbase.

A pad used for applying a priming solution becomes soiled after a whileand easy replacement of pads is desirable. It is therefore advantageousfor the priming ap paratus to be so constructed that the pad is readilyremovable therefrom. Thus, although the said pad could, for example, bea sleeve on said tube and the latter arranges so that such sleeve couldreadily be slipped off one end of the tube and a replacement sleeveslipped thereover, preferably, according to a further feature of thisinvention, the said pad is a simple flat length of suitable materialwhich is bent into arcuate form over a portion of the periphery of thetube so that part of the pad projects therefrom in a position to engagethe plate cylinder, when the tube is moved to its operative position,and which is clamped against the tube by readily releasable means.

Advantageously, the tube is movable between its operative andout-of-the-way positions by means of an operating lever and the saidclamping means are arranged to be released by movement of said operatinglever beyond the position it occupies when the tube is in itsout-of-the-way position.

Conveniently, a latch lever bears on a pin carried by a clamping memberarranged over the pad, such latch lever having therein a slot into whichsaid pin locks when the tube is moved away from the plate cylinderbeyond its out-of-the-way position so as thereafter to hold the clampingmember against movement, whereby movement of the tube in the oppositedirection moves this and the pad away from the clamping member. v

Conveniently the closing of the clamping means may also be arranged tobe effected by movement of the operating lever,

In order that this invention may more readily be understood, oneapparatus incorporating the invention will now be described by way ofexample with reference to the accompanying drawings, in which: v

FIGURE 1 is a diagrammatic side elevation of this embodiment with thepriming tube in its out-of-the-way position, and

FIGURE 2 is a similar view with the priming tube in its operativeposition.

Referring to the drawings, this embodiment comprises a cylindricalpriming tube 1 which extends across the width of the offset rotaryprinting machine adjacent the plate cylinder 2 thereof and is carried ateach end on side members 3 in the form of elongate arms which at one endare secured to the tube 1 and at the other end are pivoted at 4 to asuitable part of the machine frame 5 so that the tube may be swung in anarcuate path towards and away from the plate cylinder 2 about an axisparallel to the axis of the latter.

Movement of the tube 1 is effected by an operating lever 6 which iscoupled to one of the said side members 3 carrying the tube at thepivoted end of such member so as to pivot with the side member and tube.This operating lever is biass'ed by a spring 7, or by any other suitablemeans, in a direction urging the tube 1 away from the plate cylinder 2and is normally held, by the engagement with a stop 8 on a suitable partof the machine frame of a catch 9 carried by the operating lever, in aposition such that the tube is in an out-of-the-way position well clearof the plate cylinder as shown in FIGURE 1. The catch 9 comprises aplate 10 slidable along the lever 6 so that the plate 10 can be movedout of engagement with the stop to enable the operating lever to bepivoted further away from the plate cylinder i.e. towards the left inFIGURE 1, for a purpose which will hereinafter be described. The catchplate 10 has at its upper end an outwardly projecting finger piece 11 ina position to be readily engageable for lifting of the plate by thefinger of an operators hand grasping the operating lever and is guidedin its movement on the lever by guide pins 12 projecting from theoperating lever engaging in a slot 13 in the catch plate. Centrally ofits length the tube 1 has a hollow spigot 14 projecting radiallyoutwardly of the tube in a direction towards the pivoting axis of thetube. The spigot communicates with the interior of the tube and hasfitted thereover a flexible tube or pipe 15, conveniently of a plasticsmaterial, which leads to a reservoir 16 carried in any suitablyconvenient position on the machine frame 5.

The reservoir 16 has the form of an inverted bottle. This bottle has inits base 17, i.e., at the top of the reservoir, a filler cap 18 providedwith a vent 19 to atmosphere. Within the neck 19 of the bottle, i.e., atthe bottom of the reservoir, is a rotary plug valve 20 which allowspriming solution in the reservoir to drip from the valve outlet 21 whenthere is a reduced pressure at such outlet. A transparent sight tube 22is fitted on the valve outlet 21 and the pipe leading to the spigot 14on the priming tube 1 is fitted on the lower end of the sight tube.

The valve has externally thereof an operating member 23 of plate form,pivoting of which about the axis of the rotary plug of the valve 20,which axis is parallel to the pivoting axis of the priming tube, causesopening and closing of the valve by rotation thereof. This valveoperating member 23 is coupled by a connecting link 24 to one of theside members 3 carrying the priming tube at the end of such side member3 at which it is connected to the tube, the arrangement being such thatmovement of the priming tube from the operative position shown in FIGURE2 to its out-of-the-way position shown in FIGURE 1 causes closing of thevalve 20 and movement of the priming tube'l from this position towardsthe plate cylinder 2 causes opening of the valve 20. The couplingbetween the connecting link 24 and the side member 3 is a slidingconnection to allow for the change of distance between the tube 1 andthe pivot of the valve operating member 23' as;the tube swings about itspivoting axis. The coupling between the connecting link 24 and the valveoperating member 23 is by means of a pin 25 on the link engaging in anarcuate slot 26 in the valve connecting member 23,.the centre ofcurvature of the slot 26 being on the pivoting axis of the valveoperating member, The pin 25 is lockable in any position in the arcuateslot 26, the pin and slot arrangement thereby enabling adjustment of thetravel of the rotary plug of the valve to be made.

The priming tube 1 has in its periphery at a position opposite that fromwhich the spigot 14 projects a line of perforations 27, such lineextending the length of the tube parallel to the axis thereof. Over thisperforated portion of the tube is bent at priming pad 28 of a suitableflexible priming solution absorbent material. The priming pad 28 in itsunbent state is of simple flat elongated rectangular form. This pad isbent round the tube 1 so that one longitudinal edge portion 29 projectstangentially of the tube downwardly towards the plate cylinder 2. Toclamp the pad 28 releasably on the tube, a clamping member 30 isprovided over said pad, this member comprising a sheet metal, e.g.,stainless steel, plate of a width to extend fully across the apparatusand having one longitudinal edge 31 curled downwardly with a radius ofcurvature slightly less than that of the periphery of the priming tubeand having at the ends of the opposite for pivoting about the pivot 4 ofthe priming tube, but

free to pivot independently of the latter. The springing of the curlededge 31 of the clamping plate over the tube clamps the pad firmlyagainst the tube. At a position above the priming tube there projectsupwardly from the clamping plate 30 centrally of the width thereof abracket 33 which carries a pin 34' engaged with the lower edge of alatch member 35 pivoted at 36 to a suitable part of the machine frameand biased downwardly by its weight. The pivoting axis of thelatchmember 35 is different from that of the priming tube, thearrangement therefore being such that, as the tube is pivoted betweenthe out-of-the-way position and the operative position in which theprojecting edge 29 ofthe pad 28 engages the plate cylinder 21, the pin34 moves back and forth along the lower edge of the latch member35, thelatter riding on the pin during the whole of this movement. I l

The latch member 35 has in its lower edge a gap leading to a slot 37 inthe member, the size of the slot 37, being such as to be capable ofreceiving the pin 34 and the position of the gap being such that the pin34 moves towards it as the tube is moved to its out-of the-way position,but has not quite reached it in the latter posir tion as is clearlyshown in FIGURE 1. When, however, the catch 9 on the operating lever israised and the oper ating lever moved beyond this position, i.e., to theleft in FIGURE 1, a stop 38 being provided to prevent excessive movementof the operating lever, the pin 34 registers with the said gap and thelatchmember moves downwardly, the pin 34 thus entering the'slot 37.Movement of the operating lever 6 downwardly again, i.e., to the rightin FIGURE 1, moves the priming tube 1 towards its operative position,but the clamping plate 30 .is held from descending by the latch member35 and the tube 1 and pad 28 move downwardly away' from the'clampingplate and enable the pad 28 to be removed and replaced. The clampingplate 30 can be released again by manually raising the latch member 35,

I claim:

1. In an offset rotary printing machine includinga plate cylinder,apparatus for applyinga. priming Solution to a plate on the cylinder,such apparatus comprising a, tube extending across the machinea'djacelnt 'the plate cylinder, a priming pad of suitable materialwrapped over at least part of said tube, said tube having perforationsover at least a part thereof covered by said pad,

1 said tube being pivotal between an operative position in waypositions, a reservoir for priming solutiomia drip feed connectionbetween said reservoir and the interior of said tube,'a rotary plugvalve in Said drip feed con.- nection, a link coupled to said tube andsaid valve and pivotal about the axis of the latter so as to berespon'siye to the movement of the tube for acting to close fthe valvewhen the tube moves to the out-of-the-way position 2. The apparatusspecified in claim 1 in which'the reservoir comprises at its bottom arestricted 'outlet, said: valve being located therein, and at its top afiller fcap having a vent therein. i j i 3. In an offset rotary printingmachine including a. plate cylinder, apparatus for applying a primingsolu tion to a plate on the cylinder, 's'uch apparatus comprising a tubeextending across the machine adjacentthe plate cylinder, a priming padof suitable material wrapped over at least a part of said tube, saidtube havingperforations over at least a part thereof covered by said pada clamping plate located above said tube and extending the lengththereof, a downwardly curled longitudinal edge portion to said plate, ofa radius of curvature slightly position in which the priming padcontacts the plate cylinder across the width thereof and anout-of-the-Way position in which said pad is spaced from the platecylinder, a reservoir for priming solution, a drip feed connectionbetween said reservoir and the interior of said tube, a valve in saiddrip feed connection and means coupling said tube to said valve andresponsive to the movement of the tube for acting to close the valvewhen the tube moves to the out-of-the-way position.

4. The apparatus specified in claim 3 and further comprising a pivotedlatch lever mounted above said plate and having a slot in its undersideand a pin carried by said clamping plate at a position above the latterand in engagement with the underside of said latch lever.

5. The apparatus specified in claim 4 and further comp-rising armscarrying said tube, a pivot on which said arms are mounted and the axisof which is parallel to said tube, said pivot being spaced from saidtube, lugs projecting from said clamping plate mounted on said pivot soas to be capable of pivoting relatively to said tube and an operatinglever connected to said arms at the position of said pivot.

6. In an offset rotary printing machine including a plate cylinder,apparatus for applying a priming solution to a plate on the cylindersuch apparatus comprising a tube which extends across the machineadjacent the plate cylinder, means for supplying a priming solution tothe interior of said tube, a priming pad of flexible priming solutionabsorbent material bent over a portion of said tube, said portion ofsaid tube being perforate, a portion of said pad projecting from thetube towards said plate cylinder, means for moving said tube between anoperative position in which the said portion of the pad engages theplate cylinder and an out-of-the-way position in which such pad portionis spaced from the plate cylinder, a clamping plate located above saidtube and extending the length thereof, and a downwardly curledlongitudinal edge portion to said plate, of a radius of curvatureslightly less than that of said tube, snap fitted onto said pad and tubeto clamp the pad against the periphery of the tube.

7. The apparatus specified in claim 6 and further comprising a pivotedlatch lever mounted above said plate and having a slot in its undersideand a pin carried by said clamping plate at a position above the latterand in engagement with the underside of said latch lever.

8. The apparatus specified in claim 7, and further comprising armscarrying said tube, a pivot on which said arms are mounted and the axisof which is parallel to said tube, said pivot being spaced from saidtube, lugs projecting from said clamping plate mounted on said pivot soas to be capable of pivoting relatively to said tube and an operatinglever connected to said arms at the position of said pivot.

9. In an ofiset rotary printing machine including a frame and a platecylinder rotatable about an axis, apparatus for applying a primingsolution to a plate on the plate cylinder, such apparatus comprisingarms pivoted on said frame about an axis parallel to the axis of theplate cylinder, a cylindrical tube extending parallel to said axis andcarried by said arms for pivoting to- 5 wards and away from said platecylinder, a reservoir for priming solution mounted on said frame andhaving a drip feed outlet at the bottom of the reservoir a valve in thebottom of the reservoir acting to control flow of solution to said dripfeed outlet, a pipe communicating said valve with the interior of saidtube, a priming pad wrapped over part of said tube, the part of saidtube over which said priming pad is wrapped being perforate, a platelocated above said tube and extending the length thereof and adownwardly curled longitudinal edge portion to said plate, of a radiusof curvature slightly less than that of said tube, snap fitted onto saidpad and tube to clamp the pad on the tube, a portion of said padprojecting downwardly from said tube towards the plate cylinder in aposition such that movement of the tube towards and away from the platecylinder moves the said pad portion from an operative position in whichit engages the plate cylinder to an out-of-the-way position spaced fromthe latter, and means linking said tube to said valve responsive tomovement of the tube to close the valve when the pad portion is in theout-of-theway position.

10. The apparatus specified in claim 9, and further comprising a pivotedlatch lever mounted above said plate and having a slot in its undersideand a pin carried by said clamping plate at a position above the latterand in engagement with the underside of said latch lever, said slotbeing positioned relatively to said pin such that movement of the tubeand pad away from the plate cylinder beyond the out-of-the-way positionof the pad moves said pin along the underside of said latch lever to theposition of said slot.

11. The apparatus specified in claim 10 and further comprising anoperating lever afiixed to one of said arms at the pivot thereof, meansbiasing said operating lever in a direction tending to move the tube andpad to the out-of-the-way position of the latte-r, a catch movable onsaid ope-rating lever and a stop on said frame in a position normally tobe engaged by said catch in the out-of-the-way position of the pad.

References Cited by the Examiner UNITED STATES PATENTS 1,861,142 5/1932Scherrer 101-157 5 2,551,601 5/1951 Hughson 101-425 2,612,105 6/1952Skinner 101-147 X 2,704,029 3/1955 George 101-425 2,965,911 12/1960Hempel et al. 101367 X ROBERT E. PULFREY, Primary Examiner.

EUGENE R. CAPOZIO, Examiner.

JULIUS R. FISHER, Assistant Examiner.

1. IN AN OFFSET ROTARY PRINTING MACHINE INCLUDING A PLATE CYLINDER,APPARATUS FOR APPLYING A PRIMING SOLUTION TO A PLATE ON THE CYLINDER,SUCH APPARATUS COMPRISING A TUBE EXTENDING ACROSS THE MACHINE ADJACENTTHE PLATE CYLINDER, A PRIMING PAD OF SUITABLE MATERIAL WRAPPED OVER ATLEAST PART OF SAID TUBE, SAID TUBE HAVING PERFORATIONS OVER AT LEAST APART THEREOF COVERED BY SAID PAD, SAID TUBE BEING PIVOTAL BETWEEN ANOPERATIVE POSITION IN WHICH THE PRIMING PAD CONTACTS THE PLATE CYLINDERACROSS THE WIDTH THEREOF AND AN OUT-OF-THE-WAY POSITION IN WHICH SAIDPAD IS SPACED FROM THE PLATE CYLINDER, MEANS FOR MOVING THE TUBE BETWEENSAID OPERATIVE AND OUT-OF-THEWAY POSITIONS, A RESERVOIR FOR PRIMINGSOLUTION, A DRIP FEED CONNECTION BETWEEN SAID RESERVOIR AND THE INTERIOROF SAID TUBE, A ROTARY PLUG VALVE IN SAID DRIP FEED CONNECTION, A LINKCOUPLED TO SAID TUBE AND SAID VALVE AND PIVOTAL ABOUT THE AXIS OF THELATTER SO AS TO BE RESPONSIVE TO THE MOVEMENT OF THE TUBE FOR ACTING TOCLOSE THE VALVE WHEN THE TUBE MOVES TO THE OUT-OF-THE-WAY POSITION.